The Brief: Sis can be an abbreviation for sister, a term of familiarity, or a ubiquitous filler-word.

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Sis can be a feminine version of the words “bro” or “dude.” Like the word dude, it can be added into a conversation at random times. The term sis has origins in communities of black women and has since become a widespread term that can be used by and refer to anyone.